Bi*ter"nate*ly

from The Collaborative International Dictionary of English v.0.48

Biternate \Bi*ter"nate\, a. [Pref. bi- + ternate.] (Bot.)
   Doubly ternate, as when a petiole has three ternate leaflets.
   -- {Bi*ter"nate*ly}, adv. --Gray.
   [1913 Webster]